This invention relates to novel 1-substituted alkyl-2-dihydro pyrazine derivatives and 1-substituted alkyl-2-hexahydro quinoxaline derivatives, which are useful as pharmaceuticals for treating circulatory and metabolic disorders. The compounds of the invention are active as platelet aggregation inhibiting, vasodilating and/or anti-lipoperoxide generating agents.
Recently, a significant number of compounds having platelet aggregation inhibiting activity have been reported. Of these, the only known compounds having a pyrazine ring as the basic structure are tetramethyl pyrazine (16th Heterocyclic Chemistry Symposium (Osaka) pp. 65-68 (1984)) and 2-higher fatty acid acyloxymethyl pyrazine (Jap. Pat. Unexam. Publ. No. 59-219269).
It is of great importance to discover high quality pharmaceuticals having stronger inhibitory activities for platelet aggregation, in order effectively to treat circulatory and metabolic disorders.
We have found that 1-substituted alkyl-2-dihydro pyrazinone derivatives and 1-substituted alkyl-2-hexahydro quinoxaline derivatives display inhibitory action on platelet aggregation, vasodilation activity and/or anti-lipoperoxide generation, and are expected to have excellent pharmaceutical properties.